A recent trial by Adicet Bio has delivered promising results. Its Phase 1 trial of gamma delta CAR-T therapy has shown the therapy to be safe and effective. Now, the company can move on to Phase 2 trials.
What is Gamma Delta CAR-T Cell Therapy For?
Gamma delta CAR-T therapy is a new cancer treatment. It uses gamma delta cells, which are T-cells that have a unique receptor. These cells are normally found in low concentrations in the body. They play a role in the initiation and spread of immune responses.
These special immune cells have the ability to recognize and kill circulating tumor cells, and infiltrate and destroy solid tumors. Importantly, they can also persist after treatment. Such properties have attracted the attention of multiple biotechnology companies.
Adicet Bio is the first of these companies to present data on a gamma delta CAR-T cell therapy trial. It used an “off-the-shelf” therapy called ADI-001, so this is also an early test case for the drug.
Why the Adicet Bio Gamma Delta CAR-T Therapy is Exciting
This study, while small, has shown very promising results. Data released in December focused on eight patients, who had refractory or relapsed B-cell non-Hodgkin’s lymphoma (NHL). These patients showed a 75 percent response rate to ADI-001, and complete response across all of the three dose levels tested.
These patients had a poor prognosis, having already had tried four other cancer therapies without success. However, four of the patients were able to be evaluated six months after receiving the ADI-001, and two of them remained free of cancer.
One of these two patients had previously been treated two times with an autologous anti-CD19 CAR-T therapy, only to end up relapsing. At the time of the repeat evaluation, he had not relapsed from the anti-cancer effects of ADI-001. This shows that the new drug from Adicet shows a major clinical benefit, says Sattva Neelapu, M.D., a professor in the Department of Lymphoma/Myeloma at The University of Texas MD Anderson Cancer Center.
More Trials are Needed
While early results are promising, the phase 1 trial was very small. This makes it so that larger tests are needed to confirm the efficacy of the drug. Neelapu says it “could be” a significant advance, but leaves plenty of room for the possibility that it won’t be.
Other positive results from the initial testing include the fact that there were no toxicities that would limit dosing, no graft-vs-host disease instances, and no reported instances of immune effector cell-associated neurotoxicity syndrome or grade 3 or higher cytokine release syndrome.
The company’s CEO, Chen Schor, was proud of the results and claimed that they showed that Adicet Bio is a pioneer in the field of gamma delta CAR-T therapy. He reiterated that there had been a 100% response rate in the trial’s patients, as well as a good durability of response.
Next up for the new drug is the identification of a recommended dosage for the phase 2 trial, which is scheduled to start in late 2022. Another study, touted as “potentially pivotal,” is set to begin in 2023.